Shaped seal bar and knife for sealing and cutting a contoured shape for a flow wrap machine

ABSTRACT

A form-fill-seal method and apparatus for wrapping food items. A form-fill-seal apparatus includes a shaped seal member and a shaped cutting knife, for example, a curved seal member and a curved cutting knife. Wrapping film is provided to the form-fill-seal machine, e.g., as a flat shape, and formed into another shape. A food item is fed into a pocket of the formed wrapping film. A shaped seal is formed in the wrapping film along a first end of the food item using the shaped seal member and cut adjacent to the shaped seal with the shaped cutting knife.

CROSS REFERENCE TO RELATED APPLICATION

This application is a divisional of co-pending U.S. application Ser. No. 10/853,918, filed May 26, 2004, priority of which is claimed under 35 U.S.C. 120, the contents of which are incorporated herein by reference as though set forth in full.

FIELD OF THE INVENTION

The present invention relates to food packaging methods and systems and, more particularly, to a form-fill-seal machine and method that utilizes a shaped seal bar and knife.

BACKGROUND

Various methods and systems have been utilized to wrap or package food products. For example, it is known to use straight seal bars to form a straight seal in a wrapping or packaging material. While these devices may be adequate for food items having straight surfaces or edges, using a straight seal bar and straight knife on a food item having a contoured shape can produce “dog ears” or other irregular shapes that extend out from the food product because the straight seal bar and knife do not make a clean seal and cut that follow the contour of the food product.

Other packages are made to conform to a shape of a food item. For example, U.S. Pat. No. 3,508,473 to Ericson describes forming a flexible bag. The bag is filled with a food item. More specifically, a web of tubular film is flattened, and straight and arcuate cuts are made along a bottom of the flattened tubular film using a blanking knife, a single die or a plurality of dies. The bottom of the bag is heat sealed. A bag formed in this manner results in a top of one flexible bag and a bottom of the next successive bag being formed with a cut in the tubular film. A food item having an irregular shape is packaged therein, and the top is sealed so that the flexible bag adheres to the food item surfaces.

Ericson, however, does not provide for a form-fill-seal method and apparatus that can be used to form a wrapping material around a food item and seal the wrapping material around the food item. Rather, the bags are made and filled or packaged in an unautomated, discontinuous manner.

Other systems have provided some so called “form-fill-seal” capabilities, but are limited and can be improved. For example, U.S. Pat. No. 6,293,073 to Caudle describes a pouch for a liquid or liquid-like product that has concave and convex “S” shaped lateral edges. The lateral edges are designed with “S” shapes to make them easier to hold compared to straight lateral edges. A pouch is made by initially folding a web material. The front and rear (top and bottom) panels of the folded material are sealed using top and bottom seal bars. The web material is fed into a second sealing mechanism. The second sealing mechanism includes seal bars and cutting mechanisms that form the “S” shaped sides or lateral edges. One “S” shaped side is initially sealed, and the pouch is filled with a fluid (water, juice, soda), a high viscosity fluid (condiment and sauce), or a fluid/solid mixtures (soups, gels, powders) through the unsealed side. The final “S” shaped side is sealed after the pouch is filled. Thus, the pouch includes four separate seals—top, bottom, and two “S” shaped side seals.

Caudle, like Ericson, does not provide for a form-fill-seal method and apparatus that can be used to form a wrapping material around a food item and seal the wrapping material in a continuous manner. Rather, Caudle describes making a pouch with “S” shaped lateral edges, and then filling the pouch with a fluid. Once the pouch is filled with the fluid, a final lateral edge is sealed. Thus, the pouch panels do not conform to a food item having a pre-defined shape since a fluid, by its nature, does not exhibit these characteristics. Thus, Caudle's asserted “form-fill-seal” capabilities are limited.

Accordingly, a need exists for a method and an apparatus that provide true form-fill-seal capabilities that can be implemented in a continuous and efficient manner in order to form, fill and seal packages with various food items, thereby improving food product appearances, processing times, costs and efficiency. The method and apparatus should utilize packaging materials that can be shaped around contours of various food items, thereby enhancing the visual appeal of the food product and eliminating “dog ears” that result from conventional processes.

SUMMARY

In accordance with one embodiment is a method of wrapping a food item. The embodiment involves providing a wrapping film to a form-fill-seal machine, forming the wrapping film, feeding the food item into an aperture or pocket defined by the formed wrapping film, forming a shaped seal in the formed wrapping film along a first end of the food item by use of the shaped seal member, and cutting the wrapping film adjacent to the shaped seal by use of the shaped cutting knife.

In another embodiment is a method of continuously forming, filling and sealing a food package with a food item. The embodiment involves transforming a wrapping film from a flat initial shape into a secondary shape while feeding the food item into an aperture or pocket defined by the wrapping film having the secondary shape, forming a first seal that joins lateral edges of the transformed wrapping film, forming a second seal in the wrapping film along a first end of the food item by use of the shaped seal bar, cutting the wrapping film having the secondary shape adjacent to the shaped seal by use of the shaped cutting knife.

In a further embodiment, A method of continuously forming, filling and sealing a food package, product package INCLUDES forming a wrapping film into a shape around a food item being fed into the shaped wrapping film, forming a shaped seal along a first end of the food item by use of the shaped seal bar, and cutting the wrapping film adjacent to the shaped seal by use of the shaped cutting knife.

In another alternative embodiment, a form-fill-seal apparatus includes a wrapping material, a collar, a lateral sealing member, a shaped seal bar, a shaped cutting knife. The wrapping material passes over the collar, which transforms the wrapping material into a second shape. The lateral sealing member receives edges of the wrapping material having the second shape and forms a lateral seal along a lateral length of the wrapping material. The shaped seal bar produces a shaped seal at a first end of the food item. The wrapping material is cut adjacent to the shaped seal by the shaped cutting knife.

In various embodiments, the shaped seal member includes a shaped top bar and a shaped bottom bar, which meet to form a shaped seal. One or both of the top and bottom bars can be heated to form a shaped heat seal. The shaped seal member and the shaped cutting knife can have curved shapes. Further, the wrapping film or material can be unrolled from a roll and shaped as needed. Various food items can be packaged including cylindrical food items, food items having a curved end, food items having a curved end and a flat end, food items having a semi-circular end, and food items having a pre-defined shape, such as a meat or meat-substitute food item.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring now to the drawings, in which like reference numbers represent corresponding parts throughout, and in which:

FIG. 1 is a perspective view of an embodiment of a form-fill-seal flow wrap machine prior to forming a shaped seal;

FIG. 2 is an alternative perspective view of FIG. 1;

FIG. 3 is a perspective view of an embodiment of a form-fill-seal flow wrap machine in the process of forming a shaped seal, and with a shaped knife cutting wrapping material along the shaped seal;

FIG. 4 is an alternative perspective view in FIG. 3;

FIG. 5 is a perspective view of an embodiment of a form-fill-seal flow wrap machine after cutting the wrapping material along a shaped seal;

FIG. 6 is an alternative perspective view of FIG. 5; and

FIG. 7 is a flow chart generally illustrating an embodiment of a form-fill-seal process for wrapping a food item.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Embodiments of a form-fill-seal apparatus having a shaped seal bar and shaped knife and form-fill-seal methods are described. In the following description, reference is made to the accompanying drawings, which show by way of illustration, and not limitation, specific embodiments which may be practiced.

FIGS. 1-6 illustrate various views of a form-fill-seal apparatus 100 at different processing stages. The apparatus 100 includes conveyors 111-113 (generally 110) upon which food items 121-123 (generally 120) are placed. A wrapping material or film 132 is unwrapped from a roll 130 and shaped or formed as a result of being passed over a or collar members 141 and 142 (generally 140). A food item 120 is fed into an aperture or pocket defined by the shaped material, and a lateral sealing member 150 applies a lateral seal along the length of the food item as the food item 120 passes below. The wrapping material 132 is then pressed or sealed with a shaped seal bar 160 and cut with a shaped knife 170. The shaped seal bar 160 and knife 170 are more closely shaped to a contoured surface of a shaped food item compared to known straight seal bars and cutting knives.

More particularly, as shown in FIGS. 1 and 2, a food item 120 is transported from a first conveyor 111 to a second conveyor 112. A wrapping material 132 is fed between the first and second conveyors 111 and 112 and provided to forming collars 140. One suitable collar 140 includes a first collar member 145 and a second collar member 146. In the illustrated embodiment, the first collar member 145 extends outward from a side of the second conveyor 111, and the second collar member 146 extends upward from the second conveyor 112. The first and second collar members 145 and 146 are triangle shapes and arranged at about 90 degrees relative to each other. Various triangle angles and configurations can be utilized. Further, collars can use other shapes besides triangles can be utilized as necessary. Thus, the collar arrangement shown in FIGS. 1-6 is provided for purposes of illustration, not limitation.

The wrapping material 132, such as cellophane or other suitable food-grade film, is initially flat as it is unwound from the roll 130. The flat wrapping material 132 is fed between first and second conveyors 110 and 111 and over collars 141 and 142, which transform the wrapping material from the flat initial shape to a second or different shape. More particularly, the wrapping material is directed over the first collar members 145, and then over the second collar members 146.

As shown, one embodiment of a lateral sealing member 150 includes a plurality of sealing wheels. In the illustrated embodiment, the sealing member 150 includes four sealing wheels 151-154 (generally 151). The wheels 151 and 152 rotate in opposite directions (one clockwise and one counterclockwise), and wheels 153 and 154 rotate in a similar manner, respectively. As a result, the lateral edges 134 of the shaped wrapping material 132 passing over the second collar members 146 are fed through the rotating wheels 151 and are joined and sealed together. In one embodiment, the lateral edges 134 of the wrapping material 132 are sealed together by the pressure applied by the wheels 151. In an alternative embodiment, the wheels 151 are heated, and heat from the wheels 151 forms a lateral heat seal 155 as the lateral edges 134 are fed through the rotating wheels 151.

While the lateral edges 134 are being fed to the sealing member 150, a food item on the first conveyor 111 is transported to the second conveyor 112. The second conveyor 112 transports the food item, which is inserted into an pocket or aperture 137 of the transformed or shaped wrapping material 132. Eventually, the food item proceeds into the wrapping material pocket 137, e.g., beneath the lateral sealing member 150.

Referring to FIGS. 3 and 4, after passing the lateral sealing member 150, a first end 126 of a food item approaches a shaped seal bar 160. The shaped wrapping material 132 can be pressed and sealed by the shaped seal bar 160.

In one embodiment, the shaped seal bar 160 is a curved seal bar that includes a curved top bar 161 and a curved bottom bar 162 or bottom, both of which are positioned at the end of the second conveyor 112 and are approximately the same shape and size. In use, the curved top bar 161 and the curved bottom bar 162 are brought together to form a curved seal 165. For example, the curved top bar 161 can be actuated downward to meet the curved bottom bar 162, the curved bottom bar 162 can be actuated upward to meat the curved top bar 161, or both the curved top and bottom bars 161 and 162 can be actuated. In the illustrated embodiment, the curved bottom bar 162 is stationary, and the curved top bar 161 is actuated downward and meets the curved bottom bar 162.

Persons of ordinary skill in the art will recognize that other shaped seal bars 160 can be utilized depending, for example, a shape, a contour, and a size of the food item being wrapped. Accordingly, a curved seal bar is merely one example of a shaped seal bar, and a curved seal bar is shown for purposes of illustration, not limitation.

As illustrated in FIGS. 1-6, a shaped cutting knife 170 is aligned with or coupled to the shaped cutting seal bar 160. In one embodiment, the shaped cutting knife 170 includes a curved base 171 and a curved blade 172 attached thereto, and the curved top bar 161 and bottom bar 162 have a shape and a size that are approximately the same as a shape and size of the curved cutting base 171 and blade 172.

The shaped knife 170 can be moveable relative to the shaped seal bar 160 so that it can be placed in “cutting” and “home” positions. Springs 174 can be used to retain the shaped cutting knife 170 in a home position or non-cutting position.

Applying pressure to or actuating the cutting knife 170 drives the curved blade 172 downward and along the outer edge of the curved top bar 161 and the curved bottom bar 162 to form a cut 175 in the shaped wrapping material 132. In other words, the curved blade 172 cuts the wrapping material 132 along the curved seal 165 formed by the curved seal bar 160. Thus, the curved seal 165 and the resulting curved cut 175 are both made along a first end 126 of the food item 120. The seal bar 160 and cutting knife 170 are then released or disengaged. At this stage, a first end 126 of the food item 120 is wrapped and sealed, and the curved seal 165 and cut 175 as formed, while a second end 127 of the food item is not yet sealed.

Referring to FIGS. 5 and 6, after sealing and cutting steps are completed, the partially wrapped food item is transported from the second conveyor 112 to the third conveyor 113. The remaining open or second end 127 can be sealed or closed off wing various techniques. For example, the second end 127 can be manually sealed together by wrapping the wrapping material 132 over the second end 127. Alternatively, the wrapping material 132 can be sealed with an appropriate machine. Shaped seal bar and knife components can also be used in a similar manner as previously discussed to seal a shaped end. In the illustrated embodiment, the second end 127 is generally flat. Accordingly, embodiments utilize a shaped seal and cut, for example, a curved seal 165 and cut 175, a lateral seal 175 extending along a length of food item, and a third or final seal 125 (not shown specifically) at the second end 127 of the food item.

The wrapping material 132 can have a flexibility that allows the wrapping film to conform to a shape of the food product. Further, the wrapping material 132 can be heat shrinkable to conform to the food item. For example, heat can be applied to the wrapped or partially wrapped food item on or after the third conveyor 113 to heat shrink the film around the food item.

Accordingly, persons of ordinary skill in the art will recognize that form-fill-seal embodiments can be used with various food items having various shapes and sizes. For example, as illustrated, one suitable food item has a generally semi-circular curved first end 126 and a generally flat second end 127. The curved first end 126 generally corresponds to the shape of the curved seal member 160 and the curved knife 170, although other seal bar and knife shapes can be utilized with different food item shapes.

The food item can also have both first and second curved ends, as previously discussed. Further, as illustrated, the food item has a cylindrical shape or cross-section. Other cross-sectional shapes can also be utilized. For example, a flat or flatter food item having a shaped or curved first end can also be utilized. Accordingly, the food item having various pre-defined shapes, including cylindrical cross sections and flat food products having one or more shaped, curved or semi-circular ends. Exemplary food products include meat or meat substitute products and sausages, but the embodiments are not so limited.

FIG. 7 is a flow chart generally illustrating method steps for implementing a form-fill-seal process according to one embodiment. It is to be understood from FIGS. 1-6 that one or more of these steps may be performed simultaneously since embodiments of a form-fill seal process can operate in a continuous and automatic manner on selected components, such as a shaped seal bar and shaped cutting knife can operate in concert.

In step 700, a food item is transported on a first conveyor. In step 705, a film is unwound from a roll, and in step 710, the film is passed over a forming collar. In step 715, the film passed over the collar is shaped or transformed from its initial shape into a second shape. In step 720, the lateral edges of the shaped film are fed to a lateral sealing member. In step 725, the food item is passed from the first conveyor to the second conveyor. In step 730, the food item on the second conveyor is delivered into a pocket or an aperture defined by the shaped wrapping film.

In step 735, a first seal (lateral seal) is formed along a length of the food item as it passes by the lateral sealing member. In step 740, a shaped seal bar, e.g., a curved seal bar is engages. In step 745, the shaped wrapping material at a first or front end of the food item is pressed by the shaped seal bar to form a shaped seal, e.g., a curved seal, as a result of the applied pressure. In step 745, in an alternative embodiment, the sealing member is heated to form a shaped heat seal.

Thus steps 740 and 745 form a second seal. In step 755, a shaped cutting knife, e.g., a curved cutting knife, is engaged in step 760, the wrapping material is cut along the shaped seal, e.g., curved seal. In step 755, the cutting knife and sealing member are disengaged or released. In step 770, the partially wrapped food item is transported from the second conveyor to the third conveyor. In step 776, the wrapping material at the second end is sealed.

Persons of ordinary skill in the art will appreciate that one or more of the above steps may be performed at the same time as other steps to provide a continuous form-fill-seal process. Accordingly, while FIG. 7 illustrates certain process steps, FIG. 7 is provided for explanation and illustration, not limitation, since various steps may be performed simultaneously to provide continuous form-fill-seal.

Persons of ordinary skill in the art will also recognize that the embodiments described herein can be utilized with various food items having various shapes and sizes including, but not limited to, meat, sausage and other encased food products. Thus the shaped seal bar and cutting knife can be designed to resemble or conform to various food contours. Further, the shaped seal member and the shaped cutting knife can have varying degrees of curvature or various curved sections to correspond to surfaces and shapes of various food items. 

1-36. (canceled)
 37. A form-fill-seal apparatus for wrapping a food item, comprising: a wrapping material; a collar; a lateral sealing member; the wrapping material passing over the collar, the collar transforming the wrapping material from a first shape into a second shape, and the lateral sealing member receiving edges of the wrapping material having the second shape to form a lateral seal along a lateral length of the wrapping material; a shaped seal bar; and a shaped cutting knife, the shaped seal bar producing a shaped seal at a first end of the food item, and the wrapping film being cut adjacent to the shaped seal by use of the shaped cutting knife.
 38. The apparatus of claim 37, the wrapping material comprising a heat-shrinkable wrapping film.
 39. The apparatus of claim 37, the wrapping material a flexible wrapping film that conforms to a shape of the food item.
 40. The apparatus of claim 37, the wrapping material being unrolled as a flat sheet and being attached to the collar, the collar transforming the flat sheet into the secondary shape.
 41. The apparatus of claim 37, transforming the wrapping film further comprising forming the wrapping film into a shape substantially corresponding to a cross-section of the food item.
 42. The apparatus of claim 37, transforming the wrapping film further comprising forming the wrapping film into a generally cylindrical shape.
 43. The apparatus of claim 37, transforming the wrapping film further comprising forming a wrapping film into a shape having a diameter that is approximately the same as a diameter of the food product.
 44. The apparatus of claim 37, the food item being directed into an aperture or pocket defined by the transformed wrapping material.
 45. The apparatus of claim 37, the collar including a first collar member and a second collar member.
 46. The apparatus of claim 45, wherein the first and second collar members are arranged approximately perpendicular to each other.
 47. The apparatus of claim 37, the lateral sealing member comprising a pair of rotating members, the lateral edges of the wrapping material being fed through the rotating members, thereby sealing together the lateral edges.
 48. The apparatus of claim 47, the pair of rotating members comprising a pair of circularly-shaped members.
 49. The apparatus of claim 47, at least one the rotating members being heated so that heat from the heated rotating member heats or melts at least one lateral edge of the wrapping material, thereby sealing together the lateral edges of the wrapping material.
 50. The apparatus of claim 37, the shaped seal member comprising a shaped top bar and a shaped bottom bar, wherein the shaped top bar and the shaped bottom bar meet to form the shaped seal.
 51. The apparatus of claim 50, at least one of the shaped top bar and the shaped bottom bar being heated.
 52. The apparatus of claim 50, the shaped top bar and the shaped bottom bar being approximately the shape and size.
 53. The apparatus of claim 50, the shaped seal member comprising a curved seal member.
 54. The apparatus of claim 37, the shaped cutting knife including a shaped cutting base and a shaped blade attached to the shaped cutting base, the shaped blade cutting the wrapping material along an outer shaped edge of the shaped seal member.
 55. The apparatus of claim 37, the shaped seal member having a shaped top bar and a shaped bottom bar, the shaped blade being proximate to an outer edge of the shaped top bar when cutting the wrapping material.
 56. The apparatus of claim 55, the shaped blade being proximate to an outer edge of the shaped bottom bar when cutting the wrapping material.
 57. The apparatus of claim 37, the shaped cutting knife being moveable relative to the shaped seal bar.
 58. The apparatus of claim 37, the shaped cutting knife being spring-loaded.
 59. The apparatus of claim 37, the shaped cutting knife comprising a curved cutting knife.
 60. The apparatus of claim 37, the wrapping material, the collar, the lateral sealing member, the shaped seal bar and the shaped cutting knife being configured so that the food item is wrapped and sealed in a continuous manner. 